text: /*
   * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without modification,
   * are permitted provided that the following conditions are met:
   *
   * 1. Redistributions of source code must retain the above copyright notice,
   *    this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright notice,
   *    this list of conditions and the following disclaimer in the documentation
   *    and/or other materials provided with the distribution.
   * 3. The name of the author may not be used to endorse or promote products
   *    derived from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
   * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
   * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
   * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
   * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
   * OF SUCH DAMAGE.
   *
   * This file is part of the lwIP TCP/IP stack.
   *
   * Author: Adam Dunkels <adam@sics.se>
   *
   */
  
  #include "lwip/sys.h"
  #include "lwip/opt.h"
  #include "lwip/def.h"
  #include "lwip/memp.h"
  
  #if (NO_SYS == 0)
  
  struct sswt_cb
  {
      s16_t timeflag;
      sys_sem_t *psem;
  };
  
  
  
  void
  sys_mbox_fetch(sys_mbox_t mbox, void **msg)
  {
    u32_t time;
    struct sys_timeouts *timeouts;
    struct sys_timeo *tmptimeout;
    sys_timeout_handler h;
    void *arg;
  
  
   again:
    timeouts = sys_arch_timeouts();
  
    if (!timeouts || !timeouts->next) {
      sys_arch_mbox_fetch(mbox, msg, 0);
    } else {
      if (timeouts->next->time > 0) {
        time = sys_arch_mbox_fetch(mbox, msg, timeouts->next->time);
      } else {
        time = SYS_ARCH_TIMEOUT;
      }
  
      if (time == SYS_ARCH_TIMEOUT) {
        /* If time == SYS_ARCH_TIMEOUT, a timeout occured before a message
     could be fetched. We should now call the timeout handler and
     deallocate the memory allocated for the timeout. */
        tmptimeout = timeouts->next;
        timeouts->next = tmptimeout->next;
        h = tmptimeout->h;
        arg = tmptimeout->arg;
        memp_free(MEMP_SYS_TIMEOUT, tmptimeout);
        if (h != NULL) {
          LWIP_DEBUGF(SYS_DEBUG, ("smf calling h=%p(%p)\n", (void *)h, (void *)arg));
        	h(arg);
        }
  
        /* We try again to fetch a message from the mbox. */
        goto again;
      } else {
        /* If time != SYS_ARCH_TIMEOUT, a message was received before the timeout
     occured. The time variable is set to the number of
     milliseconds we waited for the message. */
        if (time <= timeouts->next->time) {
    timeouts->next->time -= time;
        } else {
    timeouts->next->time = 0;
        }
      }
  
    }
  }
  
  void
  sys_sem_wait(sys_sem_t sem)
  {
    u32_t time;
    struct sys_timeouts *timeouts;
    struct sys_timeo *tmptimeout;
    sys_timeout_handler h;
    void *arg;
  
    /*  while (sys_arch_sem_wait(sem, 1000) == 0);
        return;*/
  
   again:
  
    timeouts = sys_arch_timeouts();
  
    if (!timeouts || !timeouts->next) {
      sys_arch_sem_wait(sem, 0);
    } else {
      if (timeouts->next->time > 0) {
        time = sys_arch_sem_wait(sem, timeouts->next->time);
      } else {
        time = SYS_ARCH_TIMEOUT;
      }
  
      if (time == SYS_ARCH_TIMEOUT) {
        /* If time == SYS_ARCH_TIMEOUT, a timeout occured before a message
     could be fetched. We should now call the timeout handler and
     deallocate the memory allocated for the timeout. */
        tmptimeout = timeouts->next;
        timeouts->next = tmptimeout->next;
        h = tmptimeout->h;
        arg = tmptimeout->arg;
        memp_free(MEMP_SYS_TIMEOUT, tmptimeout);
        if (h != NULL) {
          LWIP_DEBUGF(SYS_DEBUG, ("ssw h=%p(%p)\n", (void *)h, (void *)arg));
          h(arg);
        }
  
  
        /* We try again to fetch a message from the mbox. */
        goto again;
      } else {
        /* If time != SYS_ARCH_TIMEOUT, a message was received before the timeout
     occured. The time variable is set to the number of
     milliseconds we waited for the message. */
        if (time <= timeouts->next->time) {
    timeouts->next->time -= time;
        } else {
    timeouts->next->time = 0;
        }
      }
  
    }
  }
  
  void
  sys_timeout(u32_t msecs, sys_timeout_handler h, void *arg)
  {
    struct sys_timeouts *timeouts;
    struct sys_timeo *timeout, *t;
  
    timeout = memp_malloc(MEMP_SYS_TIMEOUT);
    if (timeout == NULL) {
      return;
    }
    timeout->next = NULL;
    timeout->h = h;
    timeout->arg = arg;
    timeout->time = msecs;
  
    timeouts = sys_arch_timeouts();
  
    LWIP_DEBUGF(SYS_DEBUG, ("sys_timeout: %p msecs=%"U32_F" h=%p arg=%p\n",
      (void *)timeout, msecs, (void *)h, (void *)arg));
  
    LWIP_ASSERT("sys_timeout: timeouts != NULL", timeouts != NULL);
  
    if (timeouts->next == NULL) {
      timeouts->next = timeout;
      return;
    }
  
    if (timeouts->next->time > msecs) {
      timeouts->next->time -= msecs;
      timeout->next = timeouts->next;
      timeouts->next = timeout;
    } else {
      for(t = timeouts->next; t != NULL; t = t->next) {
        timeout->time -= t->time;
        if (t->next == NULL || t->next->time > timeout->time) {
          if (t->next != NULL) {
            t->next->time -= timeout->time;
          }
          timeout->next = t->next;
          t->next = timeout;
          break;
        }
      }
    }
  
  }
  
  /* Go through timeout list (for this task only) and remove the first matching entry,
     even though the timeout has not triggered yet.
  */
  
  void
  sys_untimeout(sys_timeout_handler h, void *arg)
  {
      struct sys_timeouts *timeouts;
      struct sys_timeo *prev_t, *t;
  
      timeouts = sys_arch_timeouts();
  
      if (timeouts->next == NULL)
          return;
  
      for (t = timeouts->next, prev_t = NULL; t != NULL; prev_t = t, t = t->next)
      {
          if ((t->h == h) && (t->arg == arg))
          {
              /* We have a match */
              /* Unlink from previous in list */
              if (prev_t == NULL)
                  timeouts->next = t->next;
              else
                  prev_t->next = t->next;
              /* If not the last one, add time of this one back to next */
              if (t->next != NULL)
                  t->next->time += t->time;
              memp_free(MEMP_SYS_TIMEOUT, t);
              return;
          }
      }
      return;
  }
  
  
  
  
  
  static void
  sswt_handler(void *arg)
  {
      struct sswt_cb *sswt_cb = (struct sswt_cb *) arg;
  
      /* Timeout. Set flag to TRUE and signal semaphore */
      sswt_cb->timeflag = 1;
      sys_sem_signal(*(sswt_cb->psem));
  }
  
  /* Wait for a semaphore with timeout (specified in ms) */
  /* timeout = 0: wait forever */
  /* Returns 0 on timeout. 1 otherwise */
  
  int
  sys_sem_wait_timeout(sys_sem_t sem, u32_t timeout)
  {
      struct sswt_cb sswt_cb;
  
      sswt_cb.psem = &sem;
      sswt_cb.timeflag = 0;
  
      /* If timeout is zero, then just wait forever */
      if (timeout > 0)
          /* Create a timer and pass it the address of our flag */
          sys_timeout(timeout, sswt_handler, &sswt_cb);
      sys_sem_wait(sem);
      /* Was it a timeout? */
      if (sswt_cb.timeflag)
      {
          /* timeout */
          return 0;
      } else {
          /* Not a timeout. Remove timeout entry */
          sys_untimeout(sswt_handler, &sswt_cb);
          return 1;
      }
  
  }
  
  
  void
  sys_msleep(u32_t ms)
  {
    sys_sem_t delaysem = sys_sem_new(0);
  
    sys_sem_wait_timeout(delaysem, ms);
  
    sys_sem_free(delaysem);
  }
  
  
  #endif /* NO_SYS */
  